The methods of the destruction of cellular tissues in situ has been used in the treatment of many diseases, or as an adjunct to surgical removal procedures. One method used requires heating the tissues, and causing them to shrink and tighten. It is often less traumatic than surgical procedures and may be the only alternative method, wherein other procedures are unsafe. Ablative treatment devices have an advantage because of the use of a destructive energy that is rapidly dissipated and reduced to a non-destructive level by conduction and convection, to forces of circulating fluids and other natural processes.
Devices using microwave energy, radiofrequency energy, ultrasonic energy, cryogenic means, laser energy, and tissues destructive substances have been used to destroy malignant, benign, and other types of cells and tissues from a wide variety of anatomic sites and organs. Tissues treated include isolated carcinoma masses and, more specifically, organs such as the prostate, glandular and stromal nodules characteristic of benign prostate hyperplasia. These devices typically include a catheter or cannula which is used to carry a radiofrequency electrode or microwave energy antenna, through a duct, to the area of treatment, and applying energy diffusively through the duct wall into the surrounding tissues in the targeted directions.
Of particular interest to the present invention are RF therapeutic protocols, which have been proven to be highly effective when used by electrophysiologists for the treatment of tachycardia; by neurosurgeons for the treatment of Parkinson's disease; and by neurosurgeons and anesthetists for other RF procedures such as Gasserian ganglionectomy for trigeminal neuralgia and percutaneous cervical cordotomy for intractable pains. Radiofrequency treatment, which exposes a patient to minimal side effects and risks, is generally performed after first locating the tissue sites for treatment. Radiofrequency energy, when coupled with a temperature control mechanism, can be supplied precisely to the device-to-tissues contact site to obtain the desired temperature for creating a lesion.
To be more efficient in RF energy ablation, an electrode with a vibration capability can be used to simultaneously deliver the massage therapy to the target tissues. The electric toothbrush with vibration has been disclosed in the following patents: Suyama in U.S. Pat. No. 4,944,296, Ng in U.S. Pat. No. 5,283,921, Hwang in U.S. Pat. No. 5,381,576, Okada in U.S. Pat. No. 5,421,726, Mei in U.S. Pat. No. 5,617,603, and Hahn in U.S. Pat. No. 5,651,157. All the above patents disclose the advantage of an electric toothbrush with vibration. However, they do not teach using an ablation electrode with vibration capability to create a lesion in the tissues for therapeutic purpose.
On the other hand, Imran in U.S. Pat. No. 5,281,218 entitled "Catheter having needle electrode for radiofrequency ablation" teaches a method using a needle electrode that is attached onto a catheter for radiofrequency ablation. Though a needle-like electrode is beneficial to ablate a tissues point for deep lesion, it is not disclosed that the particular needle electrode could possibly combine pressure therapy for proper contact with the target tissues. The "pressure therapy" is defined in this invention as the application of significant pressure onto the tissues by a medical device.
Edwards et al. in U.S. Pat. No. 5,456,662 entitled "Method for reducing snoring by RF ablation of the uvula" teaches a medical ablation method for reducing snoring wherein a flexible RF electrode wire is inserted into the uvula and RF energy is applied to the uvula tissues to cause internal lesions. Edwards et al. does not disclose a catheter to ablate tissues, having the capability for simultaneously delivering radiofrequency energy and pressure therapy.
Therefore, there is a need for an improved medical device and methods using the radiofrequency energy to treat uvular, polyps, or tumors, while applying pressure and/or vibrational massage therapy.